Im not Tactical Ted or a Ninja Master & do not espouse the "way of the Warrior" belief system but I have heard-read a few sources that say; "if you get into a knife fight you will get cut.

Id suggest a small, sharp Tanto type blade that can gash, cut, stab quickly.
The slick Ka-Bar TDI tanto comes to my mind.
The tall female could carry-deploy the pistol then in a CQB/point blank attack, pull out the TDI & use it.

If she has the space, $$$, etc she should practice these CQB tactics(gun & blade) with a CPR dummy or human size polymer-rubber training aid.
To "attack" milk jugs filled with red-guts like goo would show her how she'd react in a dynamic, high stress event.

CF
ps: Many, many years ago, as a young US Army MP, a E-6/SSG in my platoon told me about a call he had in Germany where a female family member killed her soldier husband with a large kitchen knife. The victim was laying(dead) at the top of the stairs/hall in a 6 story apt bldg. The MP Sgt told me the victim's blood(a lot of it) flowed all the way to the front door/first floor!